Free JSON Tool · Validate · Beautify · Minify
Free JSON Formatter & Validator Online
Paste minified or ugly JSON and instantly beautify it with 2-space, 4-space, or tab indentation. Validates syntax, highlights errors, minifies for production, and sorts keys alphabetically.
Why Format JSON?
APIs return minified JSON to save bandwidth — but it's impossible to read or debug. Our JSON formatter adds proper indentation, newlines, and spacing to make complex JSON structures immediately readable. It also validates JSON syntax and reports the exact line and position of errors, saving hours of debugging time. Use the minify feature to reverse this for production API payloads.
Features
Format / Beautify
Add indentation and newlines to minified JSON. Choose 2-space, 4-space, or tab indentation.
Minify
Strip whitespace and compress JSON to one line for API responses and production builds.
Sort Keys
Sort all object keys alphabetically — great for code reviews and spotting differences.
Validate
Instantly detect syntax errors with the exact error message. Catches trailing commas, missing quotes, etc.
FAQ — JSON Formatter
What is JSON formatting / beautifying?
JSON formatting adds indentation, line breaks, and spacing to compact JSON to make it human-readable. It does not change the data — only the whitespace.
What errors does the JSON validator catch?
Missing or extra commas, missing closing brackets/braces, unquoted keys, single-quoted strings, trailing commas, and invalid value types. The browser's JSON.parse() is used, so it catches all spec violations.
What is the difference between Format and Minify?
Format adds whitespace to make JSON readable. Minify removes all whitespace to make JSON as compact as possible — useful for reducing API payload size and network transfer time.
Does "Sort Keys" change my data?
No. Sort Keys only changes the order of object keys — the values are not altered. JavaScript objects are unordered by spec, so sorting is safe and does not affect functionality.
Can I use this for large JSON files?
Yes — the tool handles JSON up to the size your browser can process in memory. For JSON over 10MB, performance may vary depending on your device.